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Subjunction/Wessel .: ">": statement-forming operator, refers to states of affairs.
- Inference (= implication)/Wessel: 2-digit predicate, relates to linguistic structures - (s) in "p>q" we do not conclude anything, but take note that a claim exists - follow-up relationship/Wessel: = implication (no operator but predicate)> paradoxes because content can be contradictory, even if the form is valid - conditional: (E.g. scientific statement) would be false for the same reason (because the content does not form a connection).
formal implication/Russell/Principia Mathematica/Wessel: "P (x)> x Q(x)": "for all x applies" corresponding "> a1a2a3..an" - binary quantifiers.
Conditional/Wessel: subjunction follows from conditional statement - (s) but not vice versa.
Logik Berlin 1999